1. Field of Invention
The present invention relates to ball joints of the type used in suspension systems of vehicles, and particularly to new side-to-side bearing socket liner halves that facilitate assembly of aftermarket suspension ball joints, and enhances ball and socket lubrication over the useful life of the joint.
2. Description of the Prior Art
Those skilled in the art will appreciate the typical construction and longevity issues related to original equipment ball joints employed in suspension and steering systems of vehicles. Such issues involve the use of techniques contributing to ease of assembly of ball joint assemblies. For example, several methods are used for securing the ball within a socket liner, assuring proper balance between torque and tightness of the joint. In applications involving oscillation, the ball and stud are permitted to rotate. If the joint is too tight, the housing and lower isn""t the socket bearing liner can be prone to cracks and or fracture, which can in turn lead to premature failure of the ball joint assembly. Usually a failure of a ball joint involves not only replacement of the ball joint; typical requirements call for the associated mating boss part to be replaced as well. Thus premature replacement of ball joint assemblies can be relatively expensive.
In suspension applications, the noted issues become potentially exacerbated by potential admission of dirt and moisture into the ball and socket to interface of the joint. Indeed, admission of dust into an exposed ball joint assembly, in combination with entrainment water vapor can be particularly deleterious to a ball joint assembly, and can lead to premature failure, particularly where ball joints are subject to relatively vigorous suspension loads, more particularly associated with off-road vehicles, such as light trucks and sports utility vehicles. Moreover, such premature deterioration of the ball joint assembly may be aggravated if the joint is subject to more than normal amounts of twisting or rotational movements about the longitudinal axis of stud.
The present invention provides an improved ball socket liner adapted to accommodate a ball and socket joint used in vehicular suspension applications subject to high structural loads, of the type encountered in off-road motoring and commonly associated with today""s 4xc3x974 light trucks and sports utility vehicles. More specifically, the improved ball and socket liner is particularly suitable for upper or lower suspension ball joint assemblies of the type used in tie rod ends adapted to oscillate, as well as articulate within limited angular ranges.
In one described embodiment, the improved socket liner for a ball and socket joint is adapted to be fixedly installed within a joint housing so as to encase the ball. The housing defines a longitudinal axis, and the liner, formed in two longitudinally extending mating halves that confront one another along surfaces parallel to the axis of the housing, are oriented to provide a theoretically tightest possible ball bearing-socket fit. Each liner half includes at least one protuberance on each longitudinally confronting surface. The protuberances not only facilitate location of the liner halves during assembly, but also assure a physical separation between the halves, creating an additional lubrication groove for enhanced operation of the joint during its useful life. In one preferred form, a compliant thin soft material cover is overmolded over the exterior socket liner structure, and exterior surface slots integrally provided on the cover interlock with protruding ribs fixed to the interior of the housing.